AdGuardHome/querylog/qlog.go

403 lines
10 KiB
Go

package querylog
import (
"fmt"
"net"
"os"
"path/filepath"
"strconv"
"strings"
"sync"
"time"
"github.com/AdguardTeam/AdGuardHome/dnsfilter"
"github.com/AdguardTeam/golibs/log"
"github.com/miekg/dns"
)
const (
queryLogFileName = "querylog.json" // .gz added during compression
getDataLimit = 500 // GetData(): maximum log entries to return
// maximum entries to parse when searching
maxSearchEntries = 50000
)
// queryLog is a structure that writes and reads the DNS query log
type queryLog struct {
conf *Config
lock sync.Mutex
logFile string // path to the log file
bufferLock sync.RWMutex
buffer []*logEntry
fileFlushLock sync.Mutex // synchronize a file-flushing goroutine and main thread
flushPending bool // don't start another goroutine while the previous one is still running
fileWriteLock sync.Mutex
}
// create a new instance of the query log
func newQueryLog(conf Config) *queryLog {
l := queryLog{}
l.logFile = filepath.Join(conf.BaseDir, queryLogFileName)
l.conf = &Config{}
*l.conf = conf
if !checkInterval(l.conf.Interval) {
l.conf.Interval = 1
}
return &l
}
func (l *queryLog) Start() {
if l.conf.HTTPRegister != nil {
l.initWeb()
}
go l.periodicRotate()
}
func (l *queryLog) Close() {
_ = l.flushLogBuffer(true)
}
func checkInterval(days uint32) bool {
return days == 1 || days == 7 || days == 30 || days == 90
}
func (l *queryLog) WriteDiskConfig(dc *DiskConfig) {
dc.Enabled = l.conf.Enabled
dc.Interval = l.conf.Interval
dc.MemSize = l.conf.MemSize
dc.AnonymizeClientIP = l.conf.AnonymizeClientIP
}
// Clear memory buffer and remove log files
func (l *queryLog) clear() {
l.fileFlushLock.Lock()
defer l.fileFlushLock.Unlock()
l.bufferLock.Lock()
l.buffer = nil
l.flushPending = false
l.bufferLock.Unlock()
err := os.Remove(l.logFile + ".1")
if err != nil && !os.IsNotExist(err) {
log.Error("file remove: %s: %s", l.logFile+".1", err)
}
err = os.Remove(l.logFile)
if err != nil && !os.IsNotExist(err) {
log.Error("file remove: %s: %s", l.logFile, err)
}
log.Debug("Query log: cleared")
}
type logEntry struct {
IP string `json:"IP"`
Time time.Time `json:"T"`
QHost string `json:"QH"`
QType string `json:"QT"`
QClass string `json:"QC"`
Answer []byte `json:",omitempty"` // sometimes empty answers happen like binerdunt.top or rev2.globalrootservers.net
OrigAnswer []byte `json:",omitempty"`
Result dnsfilter.Result
Elapsed time.Duration
Upstream string `json:",omitempty"` // if empty, means it was cached
}
func (l *queryLog) Add(params AddParams) {
if !l.conf.Enabled {
return
}
if params.Question == nil || len(params.Question.Question) != 1 || len(params.Question.Question[0].Name) == 0 ||
params.ClientIP == nil {
return
}
if params.Result == nil {
params.Result = &dnsfilter.Result{}
}
now := time.Now()
entry := logEntry{
IP: l.getClientIP(params.ClientIP.String()),
Time: now,
Result: *params.Result,
Elapsed: params.Elapsed,
Upstream: params.Upstream,
}
q := params.Question.Question[0]
entry.QHost = strings.ToLower(q.Name[:len(q.Name)-1]) // remove the last dot
entry.QType = dns.Type(q.Qtype).String()
entry.QClass = dns.Class(q.Qclass).String()
if params.Answer != nil {
a, err := params.Answer.Pack()
if err != nil {
log.Info("Querylog: Answer.Pack(): %s", err)
return
}
entry.Answer = a
}
if params.OrigAnswer != nil {
a, err := params.OrigAnswer.Pack()
if err != nil {
log.Info("Querylog: OrigAnswer.Pack(): %s", err)
return
}
entry.OrigAnswer = a
}
l.bufferLock.Lock()
l.buffer = append(l.buffer, &entry)
needFlush := false
if !l.flushPending {
needFlush = len(l.buffer) >= int(l.conf.MemSize)
if needFlush {
l.flushPending = true
}
}
l.bufferLock.Unlock()
// if buffer needs to be flushed to disk, do it now
if needFlush {
// write to file
// do it in separate goroutine -- we are stalling DNS response this whole time
go l.flushLogBuffer(false) // nolint
}
}
// Parameters for getData()
type getDataParams struct {
OlderThan time.Time // return entries that are older than this value
Domain string // filter by domain name in question
Client string // filter by client IP
QuestionType string // filter by question type
ResponseStatus responseStatusType // filter by response status
StrictMatchDomain bool // if Domain value must be matched strictly
StrictMatchClient bool // if Client value must be matched strictly
}
// Response status
type responseStatusType int32
// Response status constants
const (
responseStatusAll responseStatusType = iota + 1
responseStatusFiltered
)
// Gets log entries
func (l *queryLog) getData(params getDataParams) map[string]interface{} {
now := time.Now()
if len(params.Client) != 0 && l.conf.AnonymizeClientIP {
params.Client = l.getClientIP(params.Client)
}
// add from file
fileEntries, oldest, total := l.searchFiles(params)
if params.OlderThan.IsZero() {
// In case if the timer is not precise (for instance, on Windows)
// We really want to get all records including those added just before the call
params.OlderThan = now.Add(time.Millisecond)
}
// add from memory buffer
l.bufferLock.Lock()
total += len(l.buffer)
memoryEntries := make([]*logEntry, 0)
// go through the buffer in the reverse order
// from NEWER to OLDER
for i := len(l.buffer) - 1; i >= 0; i-- {
entry := l.buffer[i]
if entry.Time.UnixNano() >= params.OlderThan.UnixNano() {
// Ignore entries newer than what was requested
continue
}
if !matchesGetDataParams(entry, params) {
continue
}
memoryEntries = append(memoryEntries, entry)
}
l.bufferLock.Unlock()
// now let's get a unified collection
entries := append(memoryEntries, fileEntries...)
if len(entries) > getDataLimit {
// remove extra records
entries = entries[:getDataLimit]
}
if len(entries) == getDataLimit {
// change the "oldest" value here.
// we cannot use the "oldest" we got from "searchFiles" anymore
// because after adding in-memory records and removing extra records
// the situation has changed
oldest = entries[len(entries)-1].Time
}
// init the response object
var data = []map[string]interface{}{}
// the elements order is already reversed (from newer to older)
for i := 0; i < len(entries); i++ {
entry := entries[i]
jsonEntry := l.logEntryToJSONEntry(entry)
data = append(data, jsonEntry)
}
log.Debug("QueryLog: prepared data (%d/%d) older than %s in %s",
len(entries), total, params.OlderThan, time.Since(now))
var result = map[string]interface{}{}
result["oldest"] = ""
if !oldest.IsZero() {
result["oldest"] = oldest.Format(time.RFC3339Nano)
}
result["data"] = data
return result
}
// Get Client IP address
func (l *queryLog) getClientIP(clientIP string) string {
if l.conf.AnonymizeClientIP {
ip := net.ParseIP(clientIP)
if ip != nil {
ip4 := ip.To4()
const AnonymizeClientIP4Mask = 24
const AnonymizeClientIP6Mask = 112
if ip4 != nil {
clientIP = ip4.Mask(net.CIDRMask(AnonymizeClientIP4Mask, 32)).String()
} else {
clientIP = ip.Mask(net.CIDRMask(AnonymizeClientIP6Mask, 128)).String()
}
}
}
return clientIP
}
func (l *queryLog) logEntryToJSONEntry(entry *logEntry) map[string]interface{} {
var msg *dns.Msg
if len(entry.Answer) > 0 {
msg = new(dns.Msg)
if err := msg.Unpack(entry.Answer); err != nil {
log.Debug("Failed to unpack dns message answer: %s: %s", err, string(entry.Answer))
msg = nil
}
}
jsonEntry := map[string]interface{}{
"reason": entry.Result.Reason.String(),
"elapsedMs": strconv.FormatFloat(entry.Elapsed.Seconds()*1000, 'f', -1, 64),
"time": entry.Time.Format(time.RFC3339Nano),
"client": l.getClientIP(entry.IP),
}
jsonEntry["question"] = map[string]interface{}{
"host": entry.QHost,
"type": entry.QType,
"class": entry.QClass,
}
if msg != nil {
jsonEntry["status"] = dns.RcodeToString[msg.Rcode]
opt := msg.IsEdns0()
dnssecOk := false
if opt != nil {
dnssecOk = opt.Do()
}
jsonEntry["answer_dnssec"] = dnssecOk
}
if len(entry.Result.Rule) > 0 {
jsonEntry["rule"] = entry.Result.Rule
jsonEntry["filterId"] = entry.Result.FilterID
}
if len(entry.Result.ServiceName) != 0 {
jsonEntry["service_name"] = entry.Result.ServiceName
}
answers := answerToMap(msg)
if answers != nil {
jsonEntry["answer"] = answers
}
if len(entry.OrigAnswer) != 0 {
a := new(dns.Msg)
err := a.Unpack(entry.OrigAnswer)
if err == nil {
answers = answerToMap(a)
if answers != nil {
jsonEntry["original_answer"] = answers
}
} else {
log.Debug("Querylog: msg.Unpack(entry.OrigAnswer): %s: %s", err, string(entry.OrigAnswer))
}
}
return jsonEntry
}
func answerToMap(a *dns.Msg) []map[string]interface{} {
if a == nil || len(a.Answer) == 0 {
return nil
}
var answers = []map[string]interface{}{}
for _, k := range a.Answer {
header := k.Header()
answer := map[string]interface{}{
"type": dns.TypeToString[header.Rrtype],
"ttl": header.Ttl,
}
// try most common record types
switch v := k.(type) {
case *dns.A:
answer["value"] = v.A.String()
case *dns.AAAA:
answer["value"] = v.AAAA.String()
case *dns.MX:
answer["value"] = fmt.Sprintf("%v %v", v.Preference, v.Mx)
case *dns.CNAME:
answer["value"] = v.Target
case *dns.NS:
answer["value"] = v.Ns
case *dns.SPF:
answer["value"] = v.Txt
case *dns.TXT:
answer["value"] = v.Txt
case *dns.PTR:
answer["value"] = v.Ptr
case *dns.SOA:
answer["value"] = fmt.Sprintf("%v %v %v %v %v %v %v", v.Ns, v.Mbox, v.Serial, v.Refresh, v.Retry, v.Expire, v.Minttl)
case *dns.CAA:
answer["value"] = fmt.Sprintf("%v %v \"%v\"", v.Flag, v.Tag, v.Value)
case *dns.HINFO:
answer["value"] = fmt.Sprintf("\"%v\" \"%v\"", v.Cpu, v.Os)
case *dns.RRSIG:
answer["value"] = fmt.Sprintf("%v %v %v %v %v %v %v %v %v", dns.TypeToString[v.TypeCovered], v.Algorithm, v.Labels, v.OrigTtl, v.Expiration, v.Inception, v.KeyTag, v.SignerName, v.Signature)
default:
// type unknown, marshall it as-is
answer["value"] = v
}
answers = append(answers, answer)
}
return answers
}